Machining flexible workpieces, such as, but not limited to, composite helicopter rotor components, is complicated by the need to restrain the workpiece with force sufficient to prevent the workpiece from moving, but without deforming the workpiece from a relaxed and/or lowest energy state. In some cases where flexible workpieces are supported and/or spatially restrained by bringing the workpiece into registration with a substantially rigid clamp, such registration and/or abutment may deform the workpiece. Machining a workpiece while deformed from a relaxed state may yield a machined workpiece that fails a tolerance inspection, particularly in parts with tight tolerances, such as aircraft parts. Each substantially rigid clamp comprises a substantially fixed clamping profile and/or clamping shape suitable for clamping only to workpieces with substantially complementary profiles and/or shapes. Accordingly, the ability to machine differently shaped workpieces may require a plurality of clamps configured to specifically complement the variously shaped workpieces.